To work around the issue, you can change the database status to offline and online. Then, you will be able to reconfigure mirroring on the database successfully. Learn about the terminology that Microsoft uses to describe software updates.

Fixes an issue that triggers errors if database mirroring is configured by Transact-SQL in SQL Server 2016 and if no database activity occurs for more than 90 seconds.

Assume that you are trying to upgrade a SQL Server 2016 mirrored instance to SQL Server 2017 by performing a rolling upgrade. After you complete upgrading, you may notice that the mirroring session is not able to synchronize. This may prevent you from completing the rolling upgrade.

Fixes an issue in which automatic failover doesn’t occur after database mirroring hangs.

Fixes an issue in which you cannot add an article to a replication publication in SQL Server 2008 or in SQL Server 2008 R2 after a failover of the replicated database. This issue occurs when the replication is configured in a database mirroring partnership.

Fixes an issue in which the startup of a database that belongs to an availability group times out in SQL Server on Linux.

Fixes an issue that causes database mirroring failover to fail with error 3456 in SQL Server 2016 or 2017.

Fixes a problem in which you receive error code 1456 when you try to add a witness to a database mirroring session in Microsoft SQL Server 2008 and in Microsoft SQL Server 2008 R2. This issue occurs when the database name is the same as an existing database mirroring session.

Fixes an assertion error issue after you establish a database mirroring session in SQL Server 2005 or SQL Server 2008 or SQL Server 2008 R2. The high-performance (asynchronous) mode is enabled in the database mirroring session.

Fixes an issue in which automatic failover doesn’t occur after database mirroring hangs.